Otkrivena su dva sigurnosna propusta u radu programskog paketa isc-dhcp. Spomenute nedostatke udaljeni napadač može iskoristiti za izvođenje DoS napada.

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Ubuntu Security Notice USN-1519-1
July 26, 2012

isc-dhcp vulnerabilities
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 12.04 LTS
- Ubuntu 11.10
- Ubuntu 11.04

Summary:

DHCP could be made to crash if it received specially crafted network
traffic.

Software Description:
- isc-dhcp: DHCP server and client

Details:

Markus Hietava discovered that the DHCP server incorrectly handled certain
malformed client identifiers. A remote attacker could use this issue to
cause DHCP to crash, resulting in a denial of service. (CVE-2012-3571)

Glen Eustace discovered that the DHCP server incorrectly handled memory. A
remote attacker could use this issue to cause DHCP to crash, resulting in a
denial of service. (CVE-2012-3954)

Update instructions:

The problem can be corrected by updating your system to the following
package versions:

Ubuntu 12.04 LTS:
  isc-dhcp-server                 4.1.ESV-R4-0ubuntu5.2

Ubuntu 11.10:
  isc-dhcp-server                 4.1.1-P1-17ubuntu10.3

Ubuntu 11.04:
  isc-dhcp-server                 4.1.1-P1-15ubuntu9.4

In general, a standard system update will make all the necessary changes.

References:
  http://www.ubuntu.com/usn/usn-1519-1
  CVE-2012-3571, CVE-2012-3954

Package Information:
  https://launchpad.net/ubuntu/+source/isc-dhcp/4.1.ESV-R4-0ubuntu5.2
  https://launchpad.net/ubuntu/+source/isc-dhcp/4.1.1-P1-17ubuntu10.3
  https://launchpad.net/ubuntu/+source/isc-dhcp/4.1.1-P1-15ubuntu9.4